Gossamer Gear Seconds Thinlight Foam Pad - 1/8"

This is the seconds (B-stock) version of Gossamer Gear's Thinlight pad, a 3 mm closed-cell polyethylene foam sheet sold at a reduced price due to minor cosmetic flaws that don't affect function. At 99 g for a 130 x 50 cm sheet, it carries an R-value of 0.5 — a modest insulation figure on its own, but that's not really the point of a pad this thin. Its real utility is as a supplement: layered under an inflatable pad it adds a bit of warmth and, more importantly, protects the inflatable's fabric from punctures caused by sharp ground debris. It also works as a standalone sit pad for breaks, or as backup insulation if a main pad fails. With no valve or baffles to worry about, there's nothing to leak or wear out over time, an advantage of foam over air-filled pads. At roughly 152 g per square meter, it's about as light as closed-cell foam gets, and buying the cosmetic-second version is a straightforward way to save money where minor surface marks don't matter.